Re: [ANNOUNCE] headergraphs - kernel header dependency visualizer

Ray Lehtiniemi
2006-09-21T14:28:17Z

On Thursday 21 September 2006 00:40, Sam Ravnborg wrote:

> Reminds me...
> Arnaldo (acme) made a few simple scripts that was based on dot.
> They are at his home directory at kernel.org.

yah, the very first commit in my tree is an import of those scripts for
reference purposes :-)

> Care to take at look at these to see if there is something to be learned.
> One good feature was that each level had a different color,
> and I recall the graphs was more dense with less (confusing?) info.

those graphs contain _much_ less information.

the primary complexity reduction mechanism in hviz appears to be that it adds
the current file to the done list immediately before it starts the
breadth-first search of the children. this eliminates the possibility of
back edges to previously seen headers, which is why those graphs flow so
nicely from left to right. unfortunately, it also discards most of the
dependency information.

my goal was to retain and present information from _all_ edges in the graph,
not just those which lead to new children. even for relatively small
hierarchies, these graphs generally wind up looking like a big ball of yarn,
which is where all the confusing colors and numbers come into play. they are
the distilled remnants of all the edges that have been pruned. only a select
few edges remain to tie the whole thing together.

ray